Final answer:
A flight itinerary should be filed with a flight service station, an air traffic control unit, or a responsible person. This ensures flight safety and adherence to aviation protocols within the civil airline infrastructure.
Step-by-step explanation:
The correct answers for the question regarding where a flight itinerary should be filed are: a flight service station, an air traffic control unit, and a responsible person. Filing a flight itinerary with these entities ensures the safety and tracking of the flight. Hence, the options are:
- a flight service station
- an air traffic control unit
- a responsible person
This is in accordance with aviation safety protocols which are pivotal to commercial passenger air traffic facilitated by the civil airline infrastructure, including airports and their control towers.